IBI376 Plus Rituximab in Patients With Untreated Indolent Lymphoma.

Follicular lymphoma (FL) and marginal zone lymphoma (MZL) are the most common inert non Hodgkin's lymphoma (iNHL). Their natural courses are slow but highly variable. The standard first-line treatment of advanced FL / MZL is based on rituximab. Whether combined with chemotherapy or not, it can induce lasting remission, but it is usually incurable. Although the first-line immunochemotherapy regimen has high efficacy, it also has high toxicity. Cytotoxic chemotherapy is related to many side effects, including bone marrow suppression and immunosuppression, gastrointestinal and cardiac toxicity, neurotoxicity and the occurrence of secondary tumors. About 20% of FL patients relapse within 2 years after first-line chemotherapy. The overall prognosis of these patients is poor. The median age of FL / MZL diagnosis is over 60 years old. These patients cannot tolerate conventional immunochemotherapy due to old age or complications. Compared with young and non complicated patients, the long-term survival is significantly reduced. Phosphatidylinositol 3-kinase (PI3K) pathway plays an important role in the occurrence and development of B-cell malignant tumors. IBI376 (INCB050465) is a second generation, effective and highly selective PI3Kδ inhibitor. Recently, the results of two key phase II clinical trials of CITADEL-203 and CITADEL-204 show that IBI376 monotherapy has a rapid and long-lasting high response rate in patients with recurrent or refractory iNHL, and is safe and tolerable. In addition, the CRONOS-3 study showed that copanlisib, an intravenous pan class I PI3K inhibitor, combined with rituximab showed better progression free survival and clinically significant improvement in objective remission rate compared with standard rituximab monotherapy in FL / MZL patients. In conclusion, we speculate that the chemotherapy free regimen of IBI376 combined with rituximab may produce deep and lasting remission in patients with FL and MZL. This is a single center, open label, single arm phase II clinical trial, which is divided into cohort A (follicular lymphoma) and cohort B (marginal zone lymphoma). The two cohorts are carried out at the same time. A total of 40 patients were treated with IBI376 combined with rituximab. The primary objective of this study is to assess the feasibility of PI3K inhibitor IBI376 in combination with rituximab in patients with untreated FL and MZL. The primary objective of this study is to assess the feasibility of PI3K inhibitor IBI376 in combination with rituximab in patients with untreated FL and MZL. The exploratory objective is to evaluate the clinical predictive biomarkers for efficacy.